new addresses, never seen by an exchange, and DIY coinjoin is all you need. I only use L2's for fun. Like zapping.
Discussion
Do you have to run a node to do your own coin join? I'm not too techy.
You don't need to "run" the node (permanently) but yes you should use BitcoinQT. Coin-control is built into Bitcoin, by design. Here's a link to a three video tutorial Fractal Encrypt made a few years ago.
https://www.youtube.com/watch?v=GGZpm7ZSakk&ab_channel=FractalEncrypt